Modular control of gait after incomplete spinal cord injury: differences between sides.

STUDY DESIGN: This is an analytical descriptive study. OBJECTIVES: The main goal of this study was to compare the modular organization of bilateral lower limb control in incomplete spinal cord injury (iSCI) patients during overground walking, using muscle synergies analysis. The secondary goal was to determine whether the similarity between the patients and control group correlate with clinical indicators of walking performance. SETTING: This study was conducted in National Hospital for Spinal Cord Injury (Toledo, Spain). METHODS: Eight iSCI patients and eight healthy subjects completed 10 walking trials at matched speed. For each trial, three-dimensional motion analysis and surface electromyography (sEMG) analysis of seven leg muscles from both limbs were performed. Muscle synergies were extracted from sEMG signals using a non-negative matrix factorization algorithm. The optimal number of synergies has been defined as the minimum number needed to obtain variability accounted for (VAF) ⩾90%. RESULTS: When compared with healthy references, iSCI patients showed fewer muscle synergies in the most affected side and, in both sides, significant differences in the composition of synergy 2. The degree of similarity of these variables with the healthy reference, together with the composition of synergy 3 of the most affected side, presented significant correlations (P<0.05) with walking performance. CONCLUSION: The analysis of muscle synergies shows potential to detect differences between the two sides in patients with iSCI. Specifically, the VAF may constitute a new neurophysiological metric to assess and monitor patients' condition throughout the gait recovery process.

Análisis biomecánico de la marcha en población pediátrica con lesión medular. Revisión de la casuística de una unidad de biomecánica hospitalaria / Biomechanic analysis of gait in the pediatric population of spinal cord injury. a review of the casuistics of a hospital biomechanics unit

Objetivo del estudio. Describir las características de los pacientes lesionados medulares en edad pediátrica cuyo patrón de marcha fue analizado en la Unidad de Biomecánica y Ayudas Técnicas del Hospital Nacional de Parapléjicos de Toledo. Material y métodos. Se realizó un estudio retrospectivo incluyendo a todos los pacientes que asistieron a la unidad, analizados entre enero de 2006 y marzo de 2010, edad inferior a 18 años, que fuesen pacientes ambulantes con/ sin ayudas técnicas e independencia de marcha con distancia mínima de 10 metros. Resultados. De los 48 pacientes incluidos en este estudio, el 53,1% eran varones frente al 46,9% de pacientes de sexo femenino. Las edades comprendidas están entre los dos años de edad hasta los 18 años, con una edad media de 12 años (+/- 2,31). La etiología de la lesión medular fue: traumática (29,16%), congénita (33,33%), neoplásica (8,33%) entre otros. En cuanto al nivel de lesión medular, en el 31,25% fueron lesiones cervicales, en el 29,16% fueron lumbares, en un 16,66% fueron dorsales, en el 2,08% fueron sacras y en el 20,83% el origen no fue medular. Conclusiones. La incidencia de lesión medular en edad pediátrica es muy pequeña, pero supone un gran reto asistencial, personal y social. La revisión bibliográfica realizada muestra la escasez de estudios referentes a esta patología y en pacientes en edades similares; así como estudios sobre el patrón de marcha que presentan estos pacientes(AU)

Objective. To describe the characteristics of patients with spinal cord injury in pediatric age whose gait pattern was analyzed in the Biomechanics and Technical Care Unit of the National Paraplegics Hospital of Toledo (Spain). Material and methods. A retrospective study including all patients attending the unit and analyzed between January 2006 and March 2010, younger than 18 years, who were outpatients with or without technical aids and independence of gait with a minimum distance of 10 meters. Results. A total of 48 patients were included in this study: 53.1% males, 46.9% female. Ages ranges from 2 to 18 years with a mean age of 12 years (+/- 2.31). The bone marrow lesion etiology was traumatic (29.16%), congenital (33.33%), neoplasm (8.33%) among others. Injury levels was cervical (31.25%), lumbar (29.16%), non-spinal origin (20.83%), dorsal (16.66%) and sacral (2.08%). Conclusion. The incidence of pediatric spinal cord injury is very small, but poses a great personal and social and care challenge. The review of the literature shows the lack of studies regarding this disease in patients of similar age as well as studies on the gait pattern in these patients(AU)

Aplicación del análisis tridimensional de la marcha en pacientes con síndrome centromedular / Application of gait 3d analysis in patients with central cord syndrome

Introducción. El síndrome centromedular es el más común de las lesiones medulares incompletas y el 87-97% de estos pacientes consiguen una marcha independiente, pero no se han encontrado estudios publicados sobre el análisis de la marcha. El objetivo de este estudio fue analizar las características de la marcha de sujetos con síndrome centromedular y comparar los resultados con un grupo control formado por individuos sanos de características antropométricas similares. Métodos. Se analizó a 12 pacientes con síndrome centromedular y a un grupo control formado por 20 sujetos. Los datos cinemáticos se obtuvieron con un sistema de análisis tridimensional del movimiento. El grupo control caminó a velocidad libre y a velocidad similar a la registrada en los pacientes. Las variables espaciotemporales y cinemáticas se compararon entre los dos grupos. Resultados. La abducción de cadera y la flexión de rodilla en el contacto inicial, así como el mínimo de flexión de rodilla durante la fase de apoyo, fueron mayores en el grupo de pacientes (p<0,05). Sin embargo, los rangos de movimiento de la rodilla y el tobillo en el plano sagital fueron mayores en el grupo control (p<0,05). Conclusiones. El patrón de la marcha de los pacientes mostró una disminución del rango de movimiento en el plano sagital de la rodilla y el tobillo y un incremento de la abducción de la cadera para incrementar la base de sustentación. Estos resultados pueden facilitar la planificación objetiva de los tratamientos encargados de mejorar la marcha en estos pacientes(AU)

Background. Central cord syndrome is the most common incomplete spinal cord injury syndrome and 87-97% of these patients achieve independent walking but no gait analysis studies have been reported. The aim of this study was to analyze the characteristics of the gait in subjects with central cord syndrome and to compare the results with a healthy anthropomorphically matched control group. Methods. Twelve patients and a control group with twenty subjects were analyzed. Kinematic data were obtained using a three-dimensional motion analysis system. The control group walked at a self-selected speed and at a speed similar to the speed previously registered in the patient group. Temporal, spatial variables and kinematic variables were compared between the two groups. Results. Hip abduction and knee flexion at initial contact as well as minimal knee flexion during stance were larger in the patient group (P<.05). However, knee and ankle ranges of motion in the sagittal plane were greater in the control group (P<.05). Conclusions. Knee and ankle range of motion in sagittal plane were reduced and hip abduction was increased to improve stability in patients with central cord syndrome. The results can support objective ways to establish the treatment to recover gait in patients with central cord syndrome(AU)

Determinación del consumo energético de la marcha en personas con alteraciones neurológicas. Revisión de los protocolos empleados / Measurement of energy cost in gait for people with neurological disorders. A review of the protocols used

Objetivo. Actualizar los conocimientos sobre las técnicas de análisis de consumo energético de la marcha en población con patología neurológica. Estrategia de búsqueda. Hasta diciembre de 2009 en las siguientes bases de datos: Medline, Physiotherapy Evidence Database, Ovid, la Biblioteca Cochrane y Sport Discus. Selección de artículos. Aquellos artículos en los que se realizaba una determinación del consumo energético de la marcha en pacientes con patología de origen neurológico y, sobre todo, en los que se describía la metodología. Se localizaron un total de 11 artículos, estructurados en 6 de parálisis cerebral, 1 de lesión cerebral traumática, 2 de ictus y 2 de lesión medular. Síntesis de resultados y conclusiones. Existe una gran disparidad en cuanto a protocolos utilizados para evaluar el consumo energético de la marcha de personas con alteraciones neurológicas. Este tipo de análisis ofrece prometedores resultados sobre la situación funcional de un paciente de forma complementaria al análisis biomecánico(AU)

Objective. To update knowledge about energy cost methods in gait for people with neurological disorders. Search strategy. We reviewed the following databases: Medline, Physiotherapy Evidence Database, Ovid, the Cochrane Library and Sport Discus up to December 2009. Study selection. Those articles in which energy cost was recorded during gait analysis in people with neurological disorders, especially those related to methodological aspects, were selected. A total of 11 articles were located. Six were related to children with cerebral palsy, 1 to traumatic brain injury, 2 to stroke and 2 to spinal cord injury. Results and conclusions. Much difference exists in regards to the protocols used to evaluate energy cost of gait in persons with neurological disorders. This type of analysis can be a useful tool to study functional performance in patients with neurological disorders complementary to the biomechanical analysis(AU)

Evaluación de la distribución de las presiones de apoyo en la interfaz usuario-cojín para determinar la presión de inflado de los cojines de aire / Evaluation of pressure support in user-cushion interface to determine inflated cushion air

Objetivo: Comprobar si la presión de inflado de los cojines antiescaras de aire en personas con lesión medular es la óptima y determinar su influencia sobre el comportamiento mecánico de los cojines. Material y métodos: Se efectuó el análisis de la distribución de presiones en la interfaz usuario-cojín con una malla de sensores capacitivos en 32 pacientes con lesión medular que disponían de cojines de aire. Se realizó un registro en las condiciones habituales de presión de inflado y otro tras realizar una corrección de ésta una vez identificada la situación óptima de distribución de presiones. Los parámetros analizados fueron los valores de presión máxima, la presión isquiática, la presión media y su desviación estándar y, en cuanto a superficies, la superficie total (Stot), la superficie que soporta una presión mayor de 60mmHg (Stot>60) y su valor porcentual (%Stot>60). Resultados: Los valores de las variables relacionadas con la presión fueron más bajos en los registros efectuados tras la corrección de la presión de inflado y, en las relacionadas con la superficie, la Stot fue más alta en el segundo registro, mientras que tanto Stot>60 y %Stot>60 fueron más bajos. En todos los casos se encontraron diferencias significativas (p<0,05). Conclusión: La diferente presión de inflado de un cojín de aire influye en la distribución de presiones en la interfaz usuario-cojín. La distribución de presiones óptima para un cojín determinado se consigue a un nivel de presión de inflado que ha de ser establecido con unos sistemas de medición objetivos (AU)

Objective: Verify if the inflation pressure of anti-bedsore air cushions in persons with bone marrow injury is optimum and determine its influence on the mechanical behavior of the cushions. Material and methods: The distribution of the user-cushion inferface was analyzed with a capacitive mesh sensor in 32 subjects with bone marrow injury who used air cushions. A recording was made of the usual conditions of inflated pressure and another one after making a correction of it once identified the optimum pressure distribution situation. Parameters analyzed were maximum pressure value (Pmax), ischiatic pressure (IschP), mean pressure (meanP) and standard deviation (SD) and, in regards to surfaces, total surface (totS), surface that supports a pressure of 60 mmHg (totS>60) and percentile value (%totS>60). Results: The values of the variables related with the pressure were lower in the recordings made after correcting for inflated pressure. In those related with surface, the TotS was higher in the second recording while the totS >60 and %totS>60 were lower. There were significant differences in all of the cases (p<0.05). Conclusion: The different inflation pressure of an air cushion influences the pressure distribution of the user-cushion interface. The distribution of the optimum pressures for a certain cushion is achieved at an inflated pressure level that must be established with some objective measurement systems (AU)

Shoulder joint kinetics during wheelchair propulsion on a treadmill at two different speeds in spinal cord injury patients.

STUDY DESIGN: Prospective study using biomechanics patient data. OBJECTIVES: To analyze shoulder joint kinetics while propelling a wheelchair placed on a treadmill and compare shoulder joint net forces and moments when changing the speed of wheelchair propulsion on the treadmill. SETTING: National Hospital for Spinal Cord Injury, Toledo, Spain. METHODS: Sixteen subjects with thoracic spinal cord injury participated. A kinematic analysis system consisting of four camcorders (Kinescan-IBV) and a kinetic device that registered the contact force of the hand on the pushrim (SMART(Wheel)) were used. The wheelchair was propelled at 3 and 4 km h(-1) without any ramp. An inverse dynamic model allowed shoulder joint net forces and moments to be calculated from the contact force of the hand on the pushrim and kinematic data. RESULTS: Increasing propulsion speed increased most of the temporal parameters of propulsion and pushrim kinetics and shoulder joint net forces and moments. Compared with other studies that used an ergometer or dynamometer at the same speed, the magnitude of the shoulder joint net forces and moments elicited by wheelchair propulsion on the treadmill were lower than obtained by wheelchair propulsion on other devices. CONCLUSION: Lower magnitude of shoulder joint forces and moments found on the treadmill may be due to the lower friction compared with the other devices reviewed. Shoulder joint forces and moments depended strongly on the propulsion speed, increasing in magnitude when speed increased from 3 to 4 km h(-1).

Comparative biomechanical gait analysis of patients with central cord syndrome walking with one crutch and two crutches.

BACKGROUND: Ambulatory people with central cord syndrome often require assistive devices. The selection of a suitable assistive device should be based on an objective assessment. Our objective in this study was to determine whether there was any difference in using two crutches over one crutch, considering that these patients have bilateral upper-limb involvement. METHODS: Kinematic gait analysis was conducted in 12 patients with central cord syndrome of more than one year of evolution and functional capacity for walking with one crutch or without crutches. Patients were asked to walk with one crutch and with two crutches at a freely chosen walking speed through a 10-m walkway. Three-dimensional kinematic equipment based on active markers was used to analyze temporospatial and articular parameters (maximum, minimum, and range of motion, ROM, throughout the cycle) FINDINGS: During two-crutch versus one-crutch walking, speed was lower (P=0041), stride time and step time were longer (P=0.004 and P=0.005) and there were fewer strides/minute and steps/minute (P=0.005 and P=0.006). The duration of the single support stance was longer during two-crutch walking (P=0.008). With respect to the articular parameters, both ankle ROMs (dorsi-plantar flexion P=0.003 and pronation-supination P=0.004) were greater with one-crutch walking than with two-crutch walking. INTERPRETATION: In patients with central cord syndrome capable of walking with one crutch or without crutches, walking with two crutches decreases speed, increases stride time and step time and improves stability by increasing single support, and diminishes ankle plantar flexion during swing phase.